import java.util.Scanner;

public class EnglishSize {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        while (scanner.hasNextLine()){
            String line = scanner.nextLine();
            if (Character.isLowerCase(line.charAt(0))){
                char c = (char) (line.charAt(0) - 32);
                System.out.println(c);
            }
            if (Character.isUpperCase(line.charAt(0))){
                char c = (char) (line.charAt(0) + 32);
                System.out.println(c);
            }
        }
    }

}
